Scientific blog
PhD report (June 2011) H.Kazimierczak  
Monday, 4 July, 2011, 17:03
Posted by Honorata Kazimierczak
In June 2011 I continued the study of hydrogen release on different surfaces from citrate solutions. Surface-limited kinetics of hydrogen release were derived for arbitrary surface coverage (alloy layers: Zn30%-Sn70%, Zn50%-Sn50%, Zn70%-Sn30%). The experiments were carried out and controlled by means of PARSTAT 2273 potentiostat. Polarization curves were determined under various hydrodynamic conditions by the rotating disc electrode technique.
I conducted research in the following solutions:
1) 0,1 M (Na3HCit+H4Cit); pH=5;
2) 0,25 M (Na3HCit+H4Cit); pH=5;
3) 0,4 M (Na3HCit+H4Cit); pH=5;
4) 0,7 M (Na3HCit+H4Cit); pH=5;
5) 0,25 M (Na3HCit+H4Cit); pH=1;
6) 0,25 M (Na3HCit+H4Cit); pH=2;
7) 0,25 M (Na3HCit+H4Cit); pH=3;
8) 0,25 M (Na3HCit+H4Cit); pH=4;
9) 0,25 M (Na3HCit+H4Cit); pH=6;
10) 0,25 M (Na3HCit+H4Cit); pH=7.

The results of all carried out tests, and plans for further research were discussed in detail with the tutor Prof. Associate. dr hab. Piotr Ozga.

In June 2011 I attended in the following seminars:
- M.Sc. Eng. Lukasz Rogal: „Technologia tiksoformowania wybranych stopow zelaza i aluminium w aspekcie ich struktury i wlasciwosci”;
- M.Sc. Eng. Michal Spisak: „Nanoskalowa funkcjonalizacja powierzchni materialow porowatych pod zasiedlanie komorkowe”;
- Professor Henryk Paul: ‘Instability of plastic flow and their role in texture transformations in fcc metals’ (third meeting);
- Associate Professor Jerzy Morgiel: 'Development, characterization and properties of composites produced with nano-materials'(second and third meeting);
- Associate Professor Marek Faryna: ‘Correlation between ceramics microstructure and functional properties’ (second and third meeting).
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PhD report (June 2011) J.Poplewska 
Monday, 4 July, 2011, 15:32
Posted by Jagoda Poplewska
1. Attending in seminars:

- M.Sc. Eng. Lukasz Rogal: „Technologia tiksoformowania wybranych stopow zelaza i aluminium w aspekcie ich struktury i wlasciwosci”;
- M.Sc. Eng. Michal Spisak: „Nanoskalowa funkcjonalizacja powierzchni materialow porowatych pod zasiedlanie komorkowe”;
- Professor Henryk Paul: ‘Instability of plastic flow and their role in texture transformations in fcc metals’ (third meeting);
- Associate Professor Jerzy Morgiel: 'Development, characterization and properties of composites produced with nano-materials'(second and third meeting);
- Associate Professor Marek Faryna: ‘Correlation between ceramics microstructure and functional properties’ (second and third meeting).

2. Continues of the training of using the scanning electron microscope for creating maps orientation (EBSD).

3. Training of using the circular saw.

4. Preparing the article: ‘Nucleation in Recristallization of fine-grained structure of aluminium alloy’ (for SIM 2011 conference) based on own research and articles:
- H. Jazaeri, F.J. Humphreys, The transition from discontinuous to continuous recrystallization in some aluminium alloys I – the deformed state, Acta Materialia 52 (2004) 3239–3250;
- H. Jazaeri, F.J. Humphreys, The transition from discontinuous to continuous recrystallization in some aluminium alloys II – the deformed state, Acta Materialia 52 (2004) 3251–3262;
- G.H. Zahid, Y. Huang, P.B. Prangnell, Microstructure and texture evolution during annealing a cryogenic-SPD processed Al-alloy with a nanoscale lamellar HAGB grain structure, Acta Materialia 57 (2009) 3509–3521.

5. Research

- Preparation of samples for observation in scanning electron microscope - the electrolytic-polishing by A2 reagent (test SEM / EBSD) and etching in order to observe the microstructure (for SEM);
- Preparation of the orientation maps of samples of aluminum after ECAP and recrystallization (T = 270 ° C and t = 1min, 0min.) using the EBSD / SEM – the works with other parameters than before (step 50 nm);
- Observations of the microstructure in the scanning electron microscope samples of aluminum after ECAP and recrystallization (T = 270 ° C and t = 1min, 0min.);
- Pressed by the curved channel angular (ECAP) samples of aluminum alloy (AA1050 and 3004) with dimensions 10x10x70mm using a testing machine INSTRON 3382. Samples pressed 2 -, 4 -, 6 - and 10-times using different routes between each test;
- Pressed by the curved channel angular (ECAP) samples of aluminum alloy (Al-Mg-Zr). Samples pressed once and then cut to the small samples with dimensions of 10x10x3mm by the circular saw and by the wire saw - and each of these samples will be subjected to another heat treatment (search for the appropriate temperature and time);
- Assisting in the round tensile specimens at elevated temperatures (400° C) on the testing machine INSTRON 6025.

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PhD report (May 2011) Marta Gajewska 
Tuesday, 7 June, 2011, 15:19
Posted by Marta Gajewska
My research in may:

I made a literature review on sintering of aluminium alloys in different atmospheres. The effectiveness of the sintering atmosphere of most of the aluminum alloys decreases in the order: nitrogen > vacuum >argon > nitrogen+hydrogen = argon+hydrogen. This indicates that the atmosphere plays an active role in the sintering of aluminium. A clue of the beneficial use of nitrogen is the formation of aluminium nitride.

In order to perform sintering in nitrogen and argon atmospheres, I tried to produce green compacts from milled 7475 alloy powder by uniaxial cold pressing at different pressures (200 – 600 MPa). Compacting turned out to be impossible without using a binder. Therefore, I decided to use 1 wt.% of glycerin addition to the powder. The optimal pressure of compacting was 300MPa.

Seminars/meetings:

Fourth meeting of “Local Composite Platform”:
- very interesting lecture on ”Composite layers and regions fabricated by in situ technique in iron and aluminum castings” given by Ewa Olejnik from Faculty of Foundry Engineering, AGH

IMMS seminars:
- “The characteristics of stress-textured areas of heterogeneous structure in selected materials and construction elements” by Sylwia Pawlak,
- “Ultra-thin multilayer polymer films as multifunctional coatings and membranes” by Tomasz Kruk.

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PhD report (May 2011) K. Stan 
Tuesday, 7 June, 2011, 14:54
Posted by Katarzyna Stan
Main studies carried out during May:

- Preparation of thin foils from Al91Mn7Fe2 ingot and melt-spun ribbons for further investigation. (The Tenupol-5 double jet electropolisher was used)
- Microscopic observation:
• Transmission Electron Microscopy
- Observation of quasicrystal-aluminium eutectic formation, confirmed by obtained 5-fold diffraction patterns, STEM analysis confirmed that is has similar composition to the quasicrystals with spherical and dendritic shape.
- Investigation of crystallographic orientation relationship between matrix and quasicrystalline phase, as a result relation i5<011>&#945; was observed in the 5-fold diffraction pattern
- Basing on analysis of quasicrystal 2-fold electron diffraction patterns quasilattice constant aR was calculated to be 0.461 nm. (which is in agreement with values obtained for quasicrystals by other researchers )
• Scanning Electron Microscopy:
- Phase and composition analysis of two recently prepared alloys
- In Al91Mn6Fe2Si1 ingot four different phases were observed:
&#945;-Al, Al6Mn, Al3(Mn,Fe) and Al4Mn.
- In Al91Mn6Fe2Zr1 ingot also 4 different phases were formed:
&#945;-Al, Al6Mn, Al3(Mn,Fe) and Al3Zr
- Preparation of melt-spun ribbons from the mentioned alloys by melt-spinning technique.
- An abstract preparation: “TEM study of the quasicrystalline phase transformation in Al-Mn-Fe melt-spun ribbon” for the 10th Multinational Congress on Microscopy (MCM 2011) in Urbino (Italy).
- Participation in seminars
performed by M.Sc. Eng. Sylwia Pawlak and M.Sc. Eng. Tomasz Kruk.


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May 2011 
Tuesday, 7 June, 2011, 14:47
Posted by Piotr Bobrowski
In May I took part in the "12th European Workshop on Modern Development and Applications in Microbeam Analysis" which was held in Angers, France. I presented a poster there, entitled “3D-EBDS investigation of Ni-Mo protective coatings”. An abstract of the poster contribution is given below. Additionally, I was taking part in 3D-EBSD measurements of a severely deformed aluminum alloy and a Ni-Mo deposit. Some results of these investigations were presented during the conference.

Abstract
P. Bobrowski, M. Faryna and A. Bigos

Hard, wear and corrosion resistant chromium coatings are widely used in aerospace, automotive and machinery industry. Despite of their excellent mechanical properties such coatings are to be eliminated from the manufacturing process due to severe toxicity of hexavalent chromium. A promising alternative to hard chromium coatings are Ni-based coatings containing refractory metals, e.g. Mo obtained from environmentally friendly ammonia-citrate electrolyte. This kind of Ni-Mo coating electrodeposited on steel substrates in a system with the rotating disk electrode under galvanostatic conditions at definite current density 4 A/dm2 was chosen for microstructure investigations. Size, shape as well as orientation of Ni-Mo crystals grown on low carbon stainless steel substrate were established in scanning electron microscope (SEM) by use of three-dimensional electron backscatter diffraction (3D EBSD) technique. It combines a regular 2D orientation imaging microscopy (OIM) with focused ion beam (FIB) sputtering. The FIB consecutively removes successive layers of the material being investigated while the EBSD/SEM acquires electron diffraction data. Such measurements were performed on Quanta 3D FEG SEM with geometrical setup employing rotating pre-tilted sample holder. Experimental parameters and measuring conditions for diffraction acquisition from coating with directionally grown Ni and Mo crystals were evaluated and optimized.

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